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/*
Java 2, v5.0 (Tiger) New Features
by Herbert Schildt
ISBN: 0072258543
Publisher: McGraw-Hill/Osborne, 2004
*/
class Gen<T> {
T ob;
Gen(T o) {
ob = o;
}
// Return ob.
T getob() {
return ob;
}
}
// A subclass of Gen.
class Gen2<T> extends Gen<T> {
Gen2(T o) {
super(o);
}
}
// Demonstrate runtime type ID implications of generic class hierarchy.
public class HierDemo3 {
public static void main(String args[]) {
// Create a Gen object for Integers.
Gen<Integer> iOb = new Gen<Integer>(88);
// Create a Gen2 object for Integers.
Gen2<Integer> iOb2 = new Gen2<Integer>(99);
// Create a Gen2 object for Strings.
Gen2<String> strOb2 = new Gen2<String>("Generics Test");
// See if iOb2 is some form of Gen2.
if(iOb2 instanceof Gen2<?>)
System.out.println("iOb2 is instance of Gen2");
// See if iOb2 is some form of Gen.
if(iOb2 instanceof Gen<?>)
System.out.println("iOb2 is instance of Gen");
System.out.println();
// See if strOb2 is a Gen2.
if(strOb2 instanceof Gen2<?>)
System.out.println("strOb is instance of Gen2");
// See if strOb2 is a Gen.
if(strOb2 instanceof Gen<?>)
System.out.println("strOb is instance of Gen");
System.out.println();
// See if iOb is an instance of Gen2, which its not.
if(iOb instanceof Gen2<?>)
System.out.println("iOb is instance of Gen2");
// See if iOb is an instance of Gen, which it is.
if(iOb instanceof Gen<?>)
System.out.println("iOb is instance of Gen");
// The following can't be compiled because
// generic type info does not exist at runtime.
// if(iOb2 instanceof Gen2<Integer>)
// System.out.println("iOb2 is instance of Gen2<Integer>");
}
}
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